Interest in the use of heteropolyoxometalate clusters as actinide complexants motivates our studies of the Preyssler heteropolytungstate anion, [NaP 5W 30O 110] 14−, and its actinide-exchanged derivatives, [AnP 5W 30O 110] n− . Under specific conditions, substitution of Na + is possible by La 3+ and Th 4+ as well as by U 4+ and the transuranics Am 3+ and Cm 3+. Both [AnP 5W 30O 110] 11− (for An≡Th 4+, U 4+) and [AnP 5W 30O 110] 12− (for An≡Am 3+, Cm 3+) as well as [LaP 5W 30O 110] 12− exhibit remarkable redox properties and form heteropoly blues. Although similar, the electrochemistry of the An 3+/La 3+- and An 4+-exchanged anions are different and distinguishable by cyclic voltammetry in aqueous mineral acid electrolytes. The synthesis of the new Preyssler anion complexes of La 3+, Th 4+, Am 3+, and Cm 3+ will be described along with results from cyclic voltammetry measurements.